Malicious PDF — malware analysis report

Static analysis result for SHA-256 b75b8a1db68160d3…

MALICIOUS

PDF

93.0 KB Created: 2021-07-27 08:34:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 09e81bc13aff544bd50a17d225381000 SHA-1: 8d6fc869d158bea1ad4215da3580b883f3933fd2 SHA-256: b75b8a1db68160d350ee33766048bc9aeb9cc9f3b4e9078de07fee22ab2bb418
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristic analysis revealed it functions as a link farm, directing users to multiple compromised WordPress upload sites and other unknown domains. The presence of numerous PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings strongly suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160cb79cbde748---wiferubuzofikove.pdf
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/7b58a8590a8b7b3e82cda214d6aefdb0/43123395020.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac948c38644---91909535652.pdf
    • http://vasvaripalmuzeum.hu/upload/file/piximesebatajumaxif.pdf
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/dd89c7b7e1130b17c7800a138b8948f0/84234494846.pdf
    • http://babyindex.nl/images/uploads/boperufefinumi.pdf
    • http://harasim.cz/uploaded/files/pejivani.pdf
    • http://bahtiyardishekimi.com/fckfiles/file/pawajaligijibofovuwenuris.pdf
    • http://ssaisarang.com/ckfinder/userfiles/files/jamikexowazogojujezi.pdf
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dfd85156ba---12195849838.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6015aaad9d---sozurawaburorup.pdf
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/7gnjifbutldssvao0h5tpfn8p6/29388426972.pdf
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607305ef0974e---20084813633.pdf
    • http://accessoriesunlimitedinc.net/catalog/file/76189594635.pdf
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/a297d9b681c57e65776fa37a185fda30/86637103869.pdf
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/09earks2dklaf58pqg6td9ge32/dawepera.pdf
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af941010bdd---57211507973.pdf
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/50919aa1a04d150d1a5777b468c91ff4/wewana.pdf
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1606cce086d3d1---2638315316.pdf
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3201cbc60---soxukusu.pdf
    • http://seabeachthailand.com/UserFiles/file/1426432509.pdf
    • http://tajesink.com/Uploadfiles/files/penukuminigiwil.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=how+does+the+dragon+eye+work+rlcraft
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec82.bin
db430d76b9bae8cb0bb422262a85a591a68c338c44e095645a34f7d6e54cd903
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC82 10944 bytes
font_01_sfnt_off000105ae.bin
8852c2a3393a232474d251ade9b2cb027770754b52efd827eb12466592e252a9
pdf-font-stream PDF embedded font (sfnt) at offset 0x105AE 17148 bytes
font_02_sfnt_off0001321e.bin
5da35c1ab0852b660d46e91df0f705e6cff73eb7a25afc02e9e1b9a76b9b0ced
pdf-font-stream PDF embedded font (sfnt) at offset 0x1321E 8788 bytes
font_03_sfnt_off00014f00.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14F00 16792 bytes